Houdini 17.5 Nodes TOP nodes

Local Scheduler TOP node

Schedules work items on the local machine.

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This node is the default scheduler that executes work items on the local machine. Works items are scheduled to run in parallel. The total number of running at once is specified by the parm Maximum CPUs to Use in combination with the job parm CPUs per Task.

Tip

If some tasks consume a lot of computational or memory resources, you can use the job parm CPUs per Task to change the maximum number of such processes that are run in parallel. For example by default if there are 8 CPUs available as determined by Maximum CPUs to Use there will be a maximum of 8 processes executed in parallel. However if CPUs per Task is set to 2 on the processor node, there will be a maximum of 4 such processes executed in parallel, with each task consuming 2 CPUs worth of resources in the scheduler.

To execute work items on a farm or remote machines, another scheduler should be utilized such as HQueue Scheduler.

Parameters

Scheduler

These are global parameters for all work items using this scheduler.

Working Directory

The relative directory where the work will be generating intermediate files and output. The intermediate files will be placed in a subdirectory. Typically $HIP is used. For running jobs on the farm, the working directory would typically be a mounted directory on all client machines, including the machine scheduling the work.

Directory Location

Select where local temporary files should be written. Files that are written here are needed for the PDG cook, but are typically not the end product, and can be removed when the cook completes. Log files and python scripts are examples of files that are typically written during the cook.

Working Directory: A pdgtemp sub directory of the Working Directory

Houdini Temp: A pdgtemp sub directory of $HOUDINI_TEMP_DIR

Custom: A custom directory specified by Custom Directory

Append PID

Adds a sub directory to the Location specified by Directory Location, which is the value of the PID (Process Identifier) of your session of Houdini. This is typically a 3-5 digit number. This is necessary if multiple sessions of Houdini are cooking TOP graphs at the same time.

Custom Directory

The full path to the temporary directory when Directory Location is set to Custom.

Maximum CPUs to Use

Specify the number of CPUs that are available for this scheduler to use to execute work items.

Use 1/4 of Total CPU Count: Use the number of logical cores divided by four.

Use All CPUs Except One: Use the number of logical cores less 1.

Use Custom CPU Count: Use the number as specified by Custom CPU Count.

Custom CPU Count

The maximum number of CPUs to use to execute work items. Positive numbers indicate how many CPUs will be used. A negative number indicates that the number of CPUs used will be the total logical cores minus the specified number.

Use HDA Pools

Enabling this will limit the number of Houdini sessions created for executing HDAProcessor work items. These sessions will be managed in a pool and reused.

HDAProcessor Pool Size

Specifies the maximum number of Houdini sessions to be created in the pool for executing HDAProcessor work items. These sessions are reused in order to reduce the overhead of creating and shutting down Houdini sessions.

Job Parms

These job specific parameters can be overridden by each node under the Local Scheduler tab on the node’s Schedulers parameter interface.

Single

Enabling this will force one work item to be executed at a time.

Use CPUs per Task

Enabling this will use the CPUs per Task value when deciding the number of CPUs to use per work item. Otherwise the work item will be assumed to consume one CPU.

CPUs per Task

The number of CPUs to use for each work item. This work item will only be run by the scheduler if at least this number of CPUs are available. The total number of CPUs available is specified by Maximum CPUs to Use.

Use Houdini Max Threads

Enabling this will set the HOUDINI_MAXTHREADS environment to the value specified in Houdini Max Threads. By default HOUDINI_MAXTHREADS is set to total number of logical cores divided by the value of Maximum CPUs to Use, which is 4 if Maximum CPUs to Use is left at it’s default value of Use 1/4 of Total CPU Count:.

Houdini Max Threads

Maximum number of threads to use for each work item in Houdini. This sets the HOUDINI_MAXTHREADS environment value.

Task Environment

Additional work item environment variables can be specified here.

Name

Name of the work item environment variable.

Value

Value of the work item environment variable.

Examples

The following examples include this node.

example_top_attributecopy Example for Attribute Copy TOP node

This example demonstrates how to copy attributes from one workitem to another.

example_top_attributecreate Example for Attribute Create TOP node

This example demonstrates how to create attributes for workitems of TOP nodes.

example_top_attributedelete Example for Attribute Delete TOP node

This example demonstrates how to delete attributes for workitems of TOP nodes.

example_top_attributefromstring Example for Attribute from String TOP node

This example demonstrates how to create attributes for workitems from a piece of string attribute coming from upstream.

example_top_csvinput Example for CSV Input TOP node

This example demonstrates how to read in data from CSV files. The CSV Input node will read CSV files and create 1 workitem per row.

example_top_csvoutput Example for CSV Output TOP node

This example demonstrates how to create a csv file from pdg work item’s attributes.

example_top_downloadfile Example for Download File TOP node

This example demonstrates how to download a file using the downloadfile node.

example_top_environmentedit Example for Environment Edit TOP node

This example demonstrates how to modify the environment variables before spawning a child process.

example_top_errorhandler Example for Error Handler TOP node

This example demonstrates how to use the Error Handler node in PDG / TOPs.

example_top_feedbackbegin Example for Block Begin Feedback TOP node

This example demonstrates how to create a feedback loop.

example_top_feedbackend Example for Block End Feedback TOP node

This example demonstrates how to create a feedback loop.

example_top_ffmpegencodevideo Example for FFmpeg Encode Video TOP node

This example demonstrates how to use FFmpeg Encode Video node to encode a sequence of images into a video file.

example_top_ffmpegextractimages Example for FFmpeg Extract Images TOP node

This example demonstrates how to use FFmpeg Extract Images node to extract images from a video file.

example_top_filecompress Example for File Compress TOP node

This example demonstrates how to compress files using TOPs / PDG.

example_top_filecopy Example for File Copy TOP node

This example demonstrates how to copy files using TOPs / PDG.

example_top_filedecompress Example for File Decompress TOP node

This example demonstrates how to decompress files using TOPs / PDG.

example_top_filepattern Example for File Pattern TOP node

This example demonstrates how to use File Pattern to load files using a match expression.

example_top_fileremove Example for File Remove TOP node

This example demonstrates how to remove a file using the Remove File node.

example_top_filerename Example for File Rename TOP node

This example demonstrates how to use the File Rename node to rename a group of files.

example_top_filterbyexpression Example for Filter By Expression TOP node

This example demonstrates how to filter upstream workitems so that the remaining set can be further processed or debugged.

example_top_forloopwithfeedback

This example demonstrates how to use the for loop with feedback construct in PDG/TOPs.

example_top_genericcommandchain

This example demonstrates how to create generic command chains.

example_top_genericgenerator Example for Generic Generator TOP node

This example demonstrates how to use generic generators to both prototype setups and to run custom command line executables.

example_top_geometryimport Example for Geometry Import TOP node

This example demonstrates how to use geometry import to interact with SOP networks by creating a workitem per detail, primitive, point, or vertex.

example_top_hdaprocessor Example for HDA Processor TOP node

This example demonstrates how to use HDA Processor to distribute HDAs using PDG/TOPs.

example_top_imagemagick Example for ImageMagick TOP node

This example demonstrates how to use Image Magick to montage and convert images.

example_top_invoke Example for Invoke TOP node

This example demonstrates how to run compiled blocks using pdg data as input.

example_top_jsoninput Example for Json Input TOP node

This example demonstrates how to use json input node to create workitems based on information contained in json files.

example_top_jsonoutput Example for Json Output TOP node

This example demonstrates how to use json output node to write workitem data to json format, or to reformat existing json files.

example_top_makedir Example for Make Directory TOP node

This example demonstrates how to use Make Dir to create directories on the system.

example_top_mapall Example for Map All TOP node

This example demonstrates how to use the Map All node to establish dependencies from everything downstream to everything upstream.

example_top_mapbyindex Example for Map by Index TOP node

This example demonstrates how to use the Map by Index node to establish dependencies from downstream to upstream based on workitem index.

example_top_mapbyrange Example for Map by Range TOP node

This example demonstrates how to use the Map by Range node to establish dependencies from downstream to upstream based on workitem index.

example_top_merge Example for Merge TOP node

This example demonstrates how to use the merge node in PDG/TOPs.

example_top_null Example for Null TOP node

This example demonstrates the usage of null nodes.

example_top_partitionall

This example demonstrates how to use the partition all node in PDG/TOPs.

example_top_partitionbyattribute Example for Partition by Attribute TOP node

This example demonstrates how to use the partition by attribute node in PDG/TOPs.

example_top_partitionbybounds Example for Partition by Bounds TOP node

This example demonstrates how to use the partition by bounds node in PDG/TOPs.

example_top_partitionbycombination Example for Partition by Combination TOP node

This example demonstrates how to use the partition by combination node in PDG/TOPs.

example_top_partitionbycomparison Example for Partition by Comparison TOP node

This example demonstrates how to use the partition by combination node in PDG/TOPs.

example_top_partitionbyexpression Example for Partition by Expression TOP node

This example demonstrates how to use the partition by expression node in PDG/TOPs.

example_top_partitionbyframe Example for Partition by Frame TOP node

This example demonstrates how to use the partition by frame node in PDG/TOPs.

example_top_partitionbyindex Example for Partition by Index TOP node

This example demonstrates how to use the partition by index node in PDG/TOPs.

example_top_partitionbynode Example for Partition by Node TOP node

This example demonstrates how to use the partition by node in PDG/TOPs.

example_top_partitionbyrange Example for Partition by Range TOP node

This example demonstrates the multiple partition options provided by the partition by range node.

example_top_partitionbytile Example for Partition by Tile TOP node

This example demonstrates how to use the partition by tile node in PDG/TOPs.

example_top_perforce Example for Perforce TOP node

This example demonstrates how to perform multiple perforce operations.

example_top_pythonmapper Example for Python Mapper TOP node

This example demonstrates how to use the Python Mapper node in PDG/TOPs.

example_top_pythonpartitioner Example for Python Partitioner TOP node

This example demonstrates how to use the Python Partitioner node in PDG/TOPs.

example_top_pythonprocessor Example for Python Processor TOP node

This example demonstrates how to use the python processor in PDG/TOPs.

example_top_pythonscript Example for Python Script TOP node

This example demonstrates how to use the Python Script node in PDG/TOPs.

example_top_renderifd Example for Render IFD TOP node

This example demonstrates how to render ifd files using the renderifd node.

example_top_ropalembic Example for ROP Alembic Output TOP node

This example demonstrates how to produce an alembic (abc) file from a sop node using the top rop alembic node.

example_top_ropcomposite Example for ROP Composite Output TOP node

This examples demonstrates how to use rop composite node to run a cop network using pdg data as input.

example_top_ropfetch Example for ROP Fetch TOP node

This example demonstrates how to use the ROP Fetch node in PDG/TOPs.

example_top_ropgeometry Example for ROP Geometry Output TOP node

This example demonstrates how to use the workitem expand node in PDG/TOPs.

example_top_ropmantra Example for ROP Mantra Render TOP node

This example demonstrates how to use the ROP Mantra node in PDG/TOPs.

example_top_sendemail Example for Send Email TOP node

This example demonstrates how to use the send email top node to send a simple e-mail.

example_top_sort Example for Sort TOP node

This example demonstrates how to use the sort node in PDG/TOPs.

example_top_split Example for Split TOP node

This example demonstrates how to use the split node in PDG/TOPs.

example_top_switch Example for Switch TOP node

This example demonstrates how to use the switch node in PDG/TOPs.

example_top_texttocsv Example for Text to CSV TOP node

This example demonstrates how to use the Text to CSV node in PDG/TOPs.

example_top_topfetch Example for TOP Fetch TOP node

This example demonstrates how to use Top Fetch to fetch results from other top networks.

example_top_topfetchinput Example for TOP Fetch Input TOP node

This example demonstrates how to use Top Fetch to fetch results from other top networks (using Top Fetch Input).

example_top_wedge Example for Wedge TOP node

This example demonstrates how to use the wedge node in PDG/TOPs.

example_top_workitemexpand Example for Work Item Expand TOP node

This example demonstrates how to use the workitem expand node in PDG/TOPs.

example_top_xmlinput Example for Xml Input TOP node

This example demonstrates how to use the xml input node in PDG/TOPs.

See also

TOP nodes